Control system and apparatus



a Z i, 1932., L EGGERT 5 V CONTROL SYSTEM AND APPARATUS Filed Aug. 50, 1929 e Sheets-Sheet 1 May 24, 1932.

L. EGGERT CONTROL SYSTEM AND APPARATUS Filed Aug. 50, 1929 6 Sheets-Sheet 2 May 24, 1932. EGGERT 1,860,022

CONTROL SYSTEM AND APPARATUS Filed Aug. 50, 1929 6 Sheets-Sheet 5 Co/v TKOL SWITCH "B May 24, 1932. 1.. EGGERT CONTROL SYSTEM AND APPARATUS Filed Aug. 30, 1929 6 Sheets-Sheet 4 May 24, 1932. EGGERT CONTROL SYSTEM AND APPARATUS Filed Aug. 30, 1929 6 Sheets-Sheet 5 MN ll 4 xii May 24, 1932.. L. EGGERT CONTROL SYSTEM AND APPARATUS Filed Aug. 30, 1929 6 Sheets-Sheet 6 zuluz Qt rim:

m F W QWW N m hi WK Es z ion: $5 5 a Patented May 24, 1932 VLEWISEGQERT, Geronimo, OHIO f conraon SYSTEM AND-AJPBARATUS Application filed Au usteo, 1929. 'Serial No. 389,392.

My invention relates to improvements in Fig. .6 is an elevation looking the ,tion-of the arrows on the line 6v 6 of'Figget;

control systems forimolding machines.

=The principal-object of my. inventionis provide an improved-system for a-utomatical? 5 ly controlling :aplurality of operating mechanismsin Suchmanner that the various operations will occur inproper sequence'and riddle support;'-

will continue forpredetermined periods time. a y V A further object is to enable an operator any stage in the automatic routine of operations of the mold making mechanisms to take control of any onset the operations for'the purpose of prolonging that operation, andto then restore the system to automatic control for subsequent operations. I

A further object is. to provide improved timing mechanism which will automatically regulate the duration and sequence ofzthe several msms.

Other oh jects of my invention willappear I 1 ally made ofmetal and is secured to or, formed hereinafter.

operations of the ;molding "mechas Fig. 1 is a general-view in elevation'of a mold making mechanism the operations which are adaptable for control my inven-fl .tiong, ,l i

Fig. 2 is an enlarged vertical section of the jolting mechanism-andthe strippers and air operated mold clamps" shown in Fig. 1 1.;

Fig. Qais a detail planoi a portion ofth mold and one of-t'he mold clamps; Fig. 2b is adetailof the mold clamp;

F .8 "is a perspective of the riddleythe riddle support, operated thereby; V

vice on the riddle support and the controlling switches F 1g. 3a is .a detail of a switch actuating-de Fig. 3bis a detail of asimilar switch actu ating device; Fig.30 IS a deta l view Fig. 4 is an enlarged plan of the panel b containing the control mechanism and tromagnetically operated switches 5 is an elevation-in the direction the arrows on the line 5-5 of Figs;

aportion the O elec- Fig. 5a is a detail of-the half-nut operating stantially on-the line 5a- 5a on Fig. 4;

* Fig. 7 .is a detail section of the"s1ide-valve on theline 7-7' of,F;ig. -4 and 'j H .Fig. .8is, a diagram of thecontrol circuits 5:.

- for the several operating-mechanisms; I

. -Referring more particularly to Figs. 2 have-shown a molding machine adapted especially formaking molds for casting car wheels. In a machine of this character the 8f;

pattern 5 is removably mounted in a horizontal position on the table of a jolting or jarring mechanism whichibumps the mold up and down to pack thejsand around the-pattern yon-d the,patternlsufiiciently toform a shoul der or flangeuponwhich the flask ;7is placed. Ihe'flask isalsojcircularjin sha-pe'andhasa 8 plurality of radial ribs which support-a ten; g tralgate memherii The 'fiask issufieiently I I larger indiametejr than the pattern. to pro-Q V Vide roomi-forthesandy8.frompWhichtheL mold is -made. In practice the. fiask js 5'.

7 brought tOQthe molding machine: and placed l in position von theimold plate by suitable or well kown handlingmecha'nism; Inlike i manner the moldwhen completed is removed from the machine suitable handlingmech-- H-IllSIIlS-a; r m

After the various operations havebeen1)er'-1. form-ed the completed :mold, including Qflask, is. stripped from the pattern, by] lifting] v orelevating' it verticallytoseparateitfrom 95 v the pattern. This is accomplished byuthe strippers 10 which arejpositioned beneath the" table of the joltinglmechanismu. V Inthe-mac'hine shown there aretwo o f'these I stripersr; p'ositionedi {diametrically r: opposite V 100 hollow and filled with oil and their lower ends have ports through which the oil 1sforced into the cylinder chambers beneath the plungers to elevate said plungers. The

supply pipe '16 communicates with the inte-.

rior' ofthe plungers at their upper ends and are connected to a source of compressed a1r. "After the strippers have been operated to elevate the completed mold and the mold has been removed, the strippers are permitted to remain in their elevated position to receive the next flask. They are then operated to lower the flask into position on the mold plate ready for the next cycle of molding operations; Air pressure for operating the strippers is controlled by a motor driven slide valve B, Figs. 1, 4 and 7, mounted in the con- I trol panel box and forming part of the control system hereinafter described.

This. valve, Fig. 7 comprises a suitable chest or box '17 connected by means of the pipe 18 to a suitable source of compressed air.

The pipe 16 extendsfrom the stripper cylinders to a port 19 in the bottom wall of the valve chest. This port is-covered or uncovered by a slide valve member 20 which also 46 con'trols 'an exhaust port 21, a chamber 22 being provided in-the valve member 20'for connecting the ports 19 and21." When the slide valvemember 20 is in the position shown in F ig..7 theport 19 is open to air under pressure from the supply thereof and the strippers will be operated to elevate the mold.

' When the slide valve member is moved to the j right of its position shown'in Fig. 7, it closes off the port 19 from the air supply'and instead connects saidport with the'exhaust port 21;.fwhereu'pon the weight of'the flask on theflstrippers moves the stripper plungers downwardly and forces the air from the sys-; tem'through the exhaust, thus lowering the flask on to the mold plate. Theexhaustpipe 23 leads from the exhaust port 21 into the top of a reservoir tank 24 and this tank has a' discharge port 25 through which the air is exhausted to the atmosphere. Any oil which is carried back to the lines from the, stripper cylinder, howevelgis accumulated in the tank Y 24 and is not washed. The lower portion of this tank isconnected by a pipe 26 to the pipe 16 leading to the stripper cylinder Fig. 1. V 'The tank is positioned above the cylinder so'that theoil which is accumulated in 14 mount- I the tank flows back to the stripper cylinder when the strippers are idle during periods between molding operations, thereby maintaining the strippers completely full of oil at all times. A check valve 27 is placed in the line 26 to prevent oil from'being forced back into the tank 24 through the pipe 26 when air is admitted to the lines 16 to elevate the strlppers. .The means just described for preventing the waste of oil and for maintaining the strippers full of oil, constitute the subject matter of my co-pending application Serial No. 389,394 of even date herewith.

- After the flask is placed in position on the mold plate and lowered to the mold plate it is clamped in this position during the process of making the mold,.and released after the mold is completed-so that the completed mold can be removed. This clamping me'chanism constitutes the subject matter of my co-pending applicationSerial No. 389,393 of even date herewith." The clamping mechanism is arranged to engage, the flask at two substantially diametrically opposite points. Air'cylinders 30 are attached to the edge of the mold plate 6, Figs. 1, 2, 2a and'2b. The cylinders have pistons 31 vertically movable therein, and both endsof the cylinders. are closed so that air pressure admitted below the pistons forces the pistons upwardly, and when admitted above the pistons the pistons will be forced downwardly. The cylinder structures are reduced at their upper ends 32 to form guides forthe enlarged ends 33 of the piston rods. The clamping arms 34 are secured to theupper endsof the piston rods and extend laterally sufficiently toengage the upper edge of the flask and clamp the flask firmly againstthe mold plate. The clamp arms have inverted cup shaped members 34 which surround the upper end por-' tlons 32 of the cylinder structures and which.

have-pins 35 engaging cam slots 36in said upper portions 32. These pin and-cam slot connections are so related that. when the clamp arms move upwardly they will rotate a quarter turn, Fig. 2a, which swings'them clear of the flask. Upon the lowering of the clamps, the clamp arms swing back into position to-engage the flaskf The lower ends of the cam slots, Fig. 2b, are disposed vertically to permit direct vertical movement for clam'pingpurposes whenthe clamp arms'are v in clamping position." The upper and lower chambers of the cylinders are connected by flexible connections 37 and 38 to the air pipes .39 and 40. The pipe 39 leads to a port 41,

Fig. 7 ,in the slide valve B and the pipe 40 leads to a port 42 in said valve. The several ports. in the valve are so related to'the slide valvemember that the ports 19 and 42 will be connected'to the exhaust port 21 and thereby relieve the stripper cylinders andthe lower chambers of the air clamp cylinders slightly before the port .41 is uncovered to admitair to the-upper chambers of the clamp cylinders. In like'mannerthe slidevalve member exhausts 'airfrom the upperclamp chambers through port tl betore admitting pressure to the ports 19 'andAQV Timingof the operation of the slide valve in this mannerdelays theoperation of the clamps until the flask has been loweredonto the mold plate, and vice versa, releases the clamps before the strippers operate to elevate the mold.

The jolting mechanism may beof any suit able type employed in molding operations of this character. The olting .mechanism' shown in the drawingsFigsLl and 2, is of a type which is operatedbyair pressure. It comprises a cylinder and a plunger d6 ver tically movabletherein. The plunger carries the supporting table 47 atits top upon which the'pattern plate and mold are mounted;

When air pressure is admitted to thecylinder below the piston, the piston israised and when the air pressure is cut ofi and the cylinder exhaust to atmosphere the plunger drops ofitsown weight and that of the'mold, striking a plurality of jarring disks d8 mounted in the frame oi the mechanism. These jolting or bumpingoperations are repeated in 6%)" I frame 57 in such mannerthat the riddle can be swung to and from a positionbver the mold. This riddle may be of any suitahle or well known type forthe purpose. The;

' one shown consists of the riddle screenf62 rapid succession to'pack the sand aroundthe,

pattern of the mold. The jolting or jarring operations are'governed by an automatic air valve 49, Fig. 1, and continued as long as air pressure is admittedto the valve 4C9. The

3 ed in the upper portion of a supportingframe 57 above the moldingmachine. A horizontal sand feeding conveyor 58 is positioned in the framevbeneath the hopper, and the. forward I end of this conveyor. is disposed over the molding machine insuch a manner that the sand will drop into the mold. .The conveyor hasa discharge chute j59rfor properly guiding f the sand into the mold. The conveyor is driven by a motor 60'through the medium of the drive chain 61.. The quantity of sand deposited into the mold is determined by the length of time of operationof the conveyor.

A riddle, Figs'l and 3, 3a, 3?) and 30 is" suspended from the outer'e'nd of asupport' ing ar1n63 which ispivot'ed at 64 on the supported by "a y okexframe, .65, in! the? upper portion of which is'ia. motor 66 1 adapted to vibrate or lshak-e' the-riddle to screen the "sand which is first sifted into "the mold: The

riddle and is us y-" e in 3 P along side the molding machineand "theoperator 1 usually deposits .a shovel full' or two of sand i ntothe' riddle while the riddle .is out" of positionp He then swings the riddle to aposition over the mo1jd,-the' riddle-is operated to sift its charge'oi' sand into the mold, and :the riddle isthenswung out of posi-m tion'prior to discharging molding sand from the conveyor58. The outer endof theriddle arm is supported by a diagonal brace 67 which is 1 also pivoted on" the frame :to

strengthen. the arm for supporting" the weight of. the riddle. The riddle'sjupportg ing-arm,'when itis out. of position, is yieldingly held by spring clip 68, Fig. 30;

mounted on the frame to" prevent accidentalmovementof the arm. Y

pThe riddlearm, init's movement intoaiid V out of position,'is arranged'to operate. a plurality of, control switches which ;are designated inFigs. 3 and; 8 asicontrolswitches Nos. 1; Qand 3. These switches are mou'ntedh on? the frame57 to beengag'ed by thea-rm' 63 in'various positiohsto whichtheYar-m is.-

iii

swung. These swit chesmay be of any suit-v able typeki Those shown in the drawings are contained .within; suitable covers or'jmen-z '1 closures and. haverolleried operating arms 69,," 70fand' 71; respectively. Switch #1 is l mounted on the frame and is operated immediately upon the movement of the riddle arm toward its position over the mold' [The arm 63 has short arm' 72 "having its end turned down to form a stop fora pivoted detent 73.

When the riddle arm begins" its' inove-ment rollered arm 69 fand o'perates' the switch. On thereturn movement of the arm, however,f'the -detent swings aboutits pivot and. rides over the switch armwith'out operating the switch. Switch' closes theicircuit,1

as hereinafter 1 described, which "brings the stripper and clamping-mechanism into operation .Cont'rol switchitfi is similar to switchcttl in construction and is positioned nearjtthe pivot6-l'i of theriddl'earm. 'jThe riddle .arm .;1- has a projection 74:.which engages the-arm 7 O J of the switch-just as the, riddlereaches'its position overthe mold, as :indicated bythe' dotted 'llIlfiS' Of the riddleljarm 63; Fig. Switch; #Qcloses acircuitwhich brings the riddle.,motor 66 into operationQand-this switch will be held closed asxlon'g as the oper ator. maintains the riddle in a position over the mold. Y

' Gontrol switch- #3 is 'similarfinconstruc I tion to switches #1 and #2 andis operated by a pivoted. detent 7 5, Figs. ,3 and 8Z2,:on the i extension 76' ofthe riddle arm. Switch its toward position, the 'detentengages the is' so positioned that asthe riddle arm is swung towards position overthe'moldthe 'detent rides. over the switch arm,71 withoutoperating said switch. Onlthe return movement ofthe riddle arm, however, towards-its idle or normal position, the'detent actuates the switch '#3 and closes a circuit which starts the operation of the sand feed ing conveyor. Control switch #3 is located so that it is actuated by the riddle arm on its return movement just after the projection 74 moves out of engagement with the arm of switch #2 whereby the riddle motor will be stoppedand the operator can swing the riddle out of. the way of the sand discharged from the sand feeding conveyor.

The control panel 80' is mounted on the frame 57 and is provided with a suitable 'cover whlch' encloses the mechanism contained therein and protects it'from dirt and damage. Within this panel enclosure is contained the timing mechanism for determining the duration of time of. the several operations hereinbefore described, together with the electromagnetical-ly operated switches for controlling the timing mechanisms. Referring more particularly to Figs. 4, and 6 the slide valve B, which controls the air for the clampsand strippers, is operated by a timing device in the panelboxBO. The valve member has an operating rod 81 which is connected to and operated by a yoke mounted to slide longitudinally on the .parallel guide rods 82.; This yoke consists of parallel cross members 83'and 84 which are'rigidly connected together by the parallel rods 85. The cross. member 84: is threaded on a screw 86'to travel back and forth along this screw when the screw is rotated. The screw is carriedon the shaft '87 which is driven in either direction by a motorhereinafter referred to as motor #1,

V the shaft being driven through the medium of asuitable reduction gear 88. I The outer end of the shaft is supported in a suitable bearing 89. When motor #1 is driven in one direction the yoke travels lengthwise out-,

wardly on the screw andoperates the slide valve member in one direction, and when the motor is reversed the yoke travels in the reverse direction on the screw and slides the valve member 20 in the opposite direction.

At the ends of its strokes the yoke engages and operates the limit switch contacts 90 and 91.*the cross members 83 being provided withan extension which engages the adjustment screws on said limit switches, Figs. 4 and 7- These limit switches are mounted on a suitable, supporting member v92 on the panel." Vhen' the partsare in normal position as shown in Figs. 4 and 7 the limit switch contacts 90 are normally held open and the contacts 91 normally closed. Shifting theyoke' to the other limit of stroke closes contacts 90 and opens contacts 91.

The length oftimerequired for the yoke to travel on the screw 86 determines'the duration of operation of the slide valve and is suflicient to, permit the operation of the clamps and strippers. r

Motor #1 has a brake drum 87 against which a brake band 87 is normally held by the spring 88, The band is connected to a release lever 88 which is operated by an electromagnet 89". The 'magnet is energized when the motor is started and de-energized when the motor is stopped. The purpose of this brake is to quickly stop the movement of the yoke and slide valve and prevent their,

overrunning the ends of their strokes. I

The circuit for motorc/qtl is established through the contacts of an electromagneti'- cally operated reversing switch C .mounted in the control panel. This switch. has two sets of contacts. One set of switch contacts 93 is operated by the electromagnet 94 to 0011-,

nect the motor wih the source of power for operating the motor in one d1rect1on.-- The other set of'contacts95 is operated by'the electromagnet 96 to reversely connect the motor with the source of power to operate.

the motor in the opposite direction. Switch contacts 97 and 98 are also operated. by the 106 of the extension 104 so as to form driving connection between the screw "and shaftwhich will permit the screw to shift longitudinally. The other'extension 105 of the screw slides in a suitable bearing 107 and atits outer end carries a cross member 108 which is guided on the guide rod 109. This cross member 108 is connected by the cables 110to a pair of weights 111, Fig. 5,

the cables pass around the pulleys 1 12 and These counter 112 on the "brackets" 113.

weights act to restore the screw to itsnormal or retracted position when it is released.

he screw is caused totravel longitudinally by a half-nut or threaded member 114. F ig. 5a, which is pivoted at 114 so that it can be swung into and out of engagement with the screw. This half-nut has a threaded portion which embraces a portion of the circumference of the screw and a "plurality of slots extend longitudinally of the screw and intersect thethreads to prevent a vac uum existing between the threads of the nut and the screw which would otherwise tend ma ta to prevent the release of the halt-nut, The

half-nut is normallyheld out of engagement with the screw by a spring and is adapted to be brought into engagement with'the screw bythe solenoid 116 when energized;

When. thescrew reaches the outer-limit of its "stroke the :endof the extension 105 strikes an adjustable stop screw on the stop arm 11? which is mounted on a horizontal rock. shaft 118 and which is yieldingly held lli'iiSfI'lOI'Hlfil position by a spring. 1119, Figs.

5 and.6.: Whenthe screw extension strikes the stop-117 it swings'the rock shaft 118 and operates a slide bar 120" which is connected at its'end to the rock. shaft by means of the 1inlt121' and the upstanding arm-122on the This-slide bar is mounted to slide longitudinally inguides 123 on an upstandingpanel support 124. This slide bar is arranged to operate two switches 125 and, 126.-

In :111SI10III15L1 position theend of the bar enmagnetically operated switch E which has contacts 121'" operated by the electromagnet 122, Fig. 4. This magnet also operates circuit for itself. I y The duration of time'of operation of the switch. contacts 125 which closes a holding jotting or jarring mechanismis controlled by a timing device F which is constructed andv operates exactly like the timing device'D just described: 7 The timing device F is'driven by motor #4 and operates a screw 1 03 which is engaged by a half-nut 114 operated by solenoi'd 11 6. .i The screw is returned to normal positi-onrby the weight 111' and cables 110. The rock shaft 128, however, which corresponds to therock shaftllS of timing device D, is connected to a slide bar 129 by means of the link 130, Fig. 5,- mounted on another-upstanding panel 131. Thi'sslide bar 129 operates only the one switch 132 by means: of its notch 133 and this switch controls the circuitof the operating electromagnet 134 of an electromagnetically operated switch G similar to the switch E.- The switchGr has switch contacts 135 which are operated by the electromagnet 13 12150 establish connectionnof motor 1 toa line: or s'ource of power. "It'also has a fourth switch contact "controlling a holding-circuit'foritselt.

The cross Imemher 108" of the dev-iceF is e'xtended laterallyand carries a pivoted detent 1'37 whichrides' over the arm 1'38 ofa'normallygopen'switch'139 on the for I ward longitudinal movement of the screw 193's} the return stroke of screw 1 03', howevenand-jnst before itreaches its normal the line or 9 position the de'tent 13? engages the member L V 138 and closes switch contacts 189. The 3010? y sure of this switch startsimotor #1 operating in thereverse direction to restore it's-screw erati onof the strippers and air-clamps to rel lease the finished mold ,and'stripthe mold.

86 to normal postien and bring about theopfrointhe pattern;

The. sequence and. dnrationf'of operations and the control of these" operations will now be described with referencemore particularly to Fig. '8. .'Inaddition-to'the.

automatically, operated switches, a push1but= ton station is provided for the -operator.= i

Thispush button station .is shown at the left hand of Fig. 8 and comprises aplural'ity of; 'push button switches placed in a positionycom These switches-are venientfor the operator. designated J, K, L, M, and P and aresarranged :so that the operator can tali e control andl'prolong any of the operations beyond the" duration automatically determined by the timing devices. The source of; current represented by the lines.L1., L2,' and L3 which" indicate 1 a .three phase alternating current system. All of the control-switches and push 1 button switches withthe exception of the push button arenormally'open and are connected to theli-ne wire-L1 by meansof theconducto-ri 14:5. i hepus'h button switchP is normally closed andis included this conductorl45 so that-upon the'operation of thispush button; P bythe operatorthe entire control circuit can be opened and :alluof ,the' mechanisrn stopped atany stag-e1 hSSlMIlQ-thflgt a fiask has been placed 'on the" strippers; The operator swings the riddle from itsjnormal position, and control switch #1-iscimmediately' closed;1 completes acircuit as (follows: conductor "14-5, a-control switch #15 conductors 146 and 147 switch,

magnet coil 96, conductor 14-8,.lim-i t-switch-91, '1 conductor 14 9, to Lil e-f the line. Switch,

magnet 96" closes the switch contacts :95 1 and,

closes the-line circuit directlyto'motor #li Motor #1 rotatesthe screw :86 and advances the yoke along said screw. Thisslides the valve member .20, ope-n-ing the stripper cylin ders to the atmosphere ancladmitsair tothe upper chambers of the clamp cylinder where- 1 upon the. strippers lower the flask onto the.

mold plate -and the clamps operate to clamp the dash in position. Theswitch magnet 96' also closes the. switch contacts .98 and com pletes a holdingycircuit for itself asffollows;

conductor 14:5, push buttongP conductors150 a V 151-and .152, to conductor 147,1tl1usi forming a" shuntifariound control switcheel; Moto13 :rom n s t per u il" reaches the limit of itss'troke andjopenslimit'f switches 91, thus breaking-the circuit through? as I switch magnet '96, cau-singthe-switch-com tacts 95 to 'open'and' stop the motor "#1,"II-i U Q starting its' movement ztlong the serewfiit, the

yoke" allows limit switch' 9-0 to close its" ' tor ,#1 to drive said motor in'the reverse disimply prepares the circuitfoi' magnet coil 94-for later operation. 1

* If the operator desires to start the motor #l-"and operate the strippers and} clamping mechanism downwardly independently of the control switch'#1 he simply presses push button switch M which closes a shunt circuit around the control switch #1 as follows: conductor145, push button switch M, conductor sition until the finished mold is to be released "from'the clamps and elevated by the strippers. r V

Normally the operator would continue swinging the riddle arm untilthe riddle 3 reached a position over the mold, whereupon ply refraining from swinging theriddle arm 7 1 ductor 149, to line L3." Switch magnet '94 directly to the line. The riddle drive motor 66-will continue to operate as long as the op@ the riddle arm would operate control switch #2 to start theriddle motor; ,However, if the operator should desire to prolong the period of time between the operation of the strippers and the riddle, he can do so by simfar enough to operate control switch #2. Furthermore, if during this prolonged pe- .riod the operator should desire to release the air clamps and operate the strippers to elevat'e the flaskhe can do so by pressing the push button L. This closes a circuit for the switch magnet 94 as followsz'conductor 145, push button switch L, conductor- 154, magnet coil 94, conductor 155, limit switch 90, concloses contacts 93, completing circuit of morection. This rotates screw 86 in the reverse Y direction and returns the'yoke to normal position, operating the slide valve member 20 to'release the air clamping mechanism and elevate the strippers. This movementof the yoke closes the limit switch 91 and opens lim-' ever, before describlng the control of the 7 it switch 90.

Returning again to the normal operation of the mechanism and assuming that the operator has swung the riddle arm, operating the control switch #1 to clamp the flask on the moldplate, he may continue to swing the riddlo arm until the riddle reaches its position over the mold and the riddle arm closes con-- trolswitch #2} This 'completes the circuit for the electromagnetically operated switch R which connects the riddle motor to the line, as follows: Line L3, conductor 157, control switch #2, magnet 156, to line L2. Switch magnet156 closesthe switchcontacts 158 and completes the circuit iforcthe riddle motor 66 holding the riddle in mold.

When he finishes operatorswings the riddle out of position and returns it to normal position with the arm 63 in engagement with the spring clips 68.

its position over the During this return movement the control switch #3 is closed by the detent 7 5,.as previously described. This completes a circuit for the sand feeding-conveyor mechanism, as follows: c'onductor'145, control switch "#3, conductor 160' and 161, switch contacts 125, magnet coil 122 of switch E, to'line L2. Magnet 122- closes switch contacts 121 and connects the line L1, L2 and L3 directly to mold #3 starting the operation of said motor;

the riddle operation the The switch magnet 122 also closes switch contacts 124 which completes a holding circuit around control switch #3 as follows:

conductor 145, push button P, conductor. 150

and 162 to conductor 161. The drive motor for the sand feedcconveyor is also started into operation because it is bridged across the line in parallel with motor. #3. The solenoid 1116 which operates the half-nut 114, as previously described, is also bridged across lines L2 and L3 by the conductor. 162. Motor #3 drives the screw 103 and the sand conveyor will continue to discharge sand intocthe mold until the screw strikes the stop 117 and opens switch contacts. 125, thus opening the circuit for switch magnet 122 whereupon the contacts 121 are open and motors #3 and #60 are stopped and the half-nut 114 disengaged fromthe screw.. Disengaging the half-nut from the screw releases the screw and permits the counter Weights. to instantly return the screw to its normal position, thereby again closing the switch contacts 125 and opening switch contacts 126. g

The bar 120 is so related to switches 125 and 126 that it closes switch 126 slightly be- I fore its notch 127 engages and opens'switch 125. The closure of the switch 126 closes a circuit for 'the. electromagnetic switch Gr which controls the jolting mechanism. Howsame circuit previouslyclosedby the control switch #3. This again energizes switch magnet 122 closing switch contacts 121"to start motor #3 and the drive motor 60 for the sand conveyor. Althoughhe may thus continue theoperation of the sand feeding mechanism indefinitelyby the operation of the switch K, to conductor 160thence over the push buttons P and K as just described, heis not likely to do so because he would not need a second full charge of sand. Instead he al-;

lows the sand conveyor to run until, a small additional quantity of sand is discharged into the moldand then stops the sand conveyor by pressing the stop button P which opens the circuit to the switch magnet122 thereby ole-energizing solenoidf116 and releasing the" screw:103. which returns to normal position. During-this second sand feeding operation the screw 108 may not have completed its full stroke to operate the bar 120 hence the switch 126 would not be closed and the jolting mechanism would not be started I automatically. Therefore, in order to start the jolting mechanism the operator would press the push but ton J completing a circuit for the magnet-- -of switch G' as follows; conductor 1 1 5, push button switch J, conductors 165 and 166,

switch contacts 132, magnet coil 134- to line L2. This magnet closes contacts135 which completes the line circuit connections lines L1, L2 and L3 directly to motor #4 of the jolting operation and timing device. Magnet 134 also closes switch contacts 136 which conipletes a holding circuit for itself around both the push button J and the switch 126 as follows: conductor 14:5, pushbutton P, conductors 150,162 and 167, switch contacts 186, to

conductor 166. The closure of the contacts 135 also energizes the solenoid 116 for the half-nut and the solenoid for air control valve 57 because both of these solenoids are bridged across lines L2 and L3 by the conductors 168.,

Thisadmits air pressure to the jolting meohanismand startsthe operation of the jolting mechanism. The duration of time of this jolting mechanism is automatically determined by the time required for the screw 103 of the timing device F to reach the outer limit of its stroke.

133' opens switch contacts 132 and breaks the circuit for magnet 13 1 thus releasing the contacts 135, stopping the motor L and de-energizing control valve solenoid 157 which stops the jolting operation. Solenoid 116" being thus (ls-energized releases the screw and permits its instant return the weights 111. On the return stroke of the yoke 103 the switch 13-9 will be momentarily closed which completes thecircuit for the magnet 9e of electromagnetically operated switch. asfollows: conductor 1&5, push but ton stop P,'conductors 150 and 162, switch, 139, conductors 170and 171, magnet 94;, con-1 ductor 155., limit switch 90, conductor 149 to line L3. The holding circuit for themagnet 9 l is-completed as follows: conductor 145, push'button P, conductor 150, conductor 172,

switch contacts '97, conductor 171 to magnet 94. Magnet 9% closescontacts 93'and starts motor dtl in thereverse direction. This re- "Nhen the screw 103" does reach the limit of its stroke it strikes the stop arm 11'?" and operates bar 129. The notch stores thescrew 86 to normal position and opcrates slide valve member 20to admit air tothe stripper cylinder. and clamps torelease the clamps and elevatethe complete mold;

The completemold is thenremoved from the stripper pins anda new flask placed on sald stripper pins.

The cycle of operations may then be repeated. k i

. If the operator wishestopprolong the opf .erationof the jolting mechanism beyond the time automatically determined by the timing" device he can do so by simplypressing the push button J. which closes the circuit for the switch magnet 134; as already described. In the event that he does prolong-the opera-. tion of the jolting mechanism for a short time but not long enough to permit the screw'1Q3 of thetiming device to reach the limit of its stroke, the switch 139 would not be operated to release the clamps and elevate the stripe at any stage of the cycle of operations can prolong any one; of the operations and-then the remaining operations. i

" I claim:

"1. In a control system of the class de scribed, the combination of asand feeding restore the system to automaticcontrol for mechanism, a jolting mechanism, means con trolllng tllQOPGILtlOIlS of said mechanisms-1n sequence, and timing .me'chanism forfdetermlnlng the duration ofoperating time of its one of said mechanisms before the commencement of operation of-the other mechanism;

2. In a control system of the: class? de scribed, a controlmember, means for moving said control member inone directiorna plurality of translating mechanismstiming de-' vices for controlling the operation of said translating mechanisms, means for returning one-of said timing devices to originaljposition after operation 1 thereof whereby said. means for moving'said control member will be operated in a direction opposite to the first operation to reposition said control mem- I 3. In a control system of the class deher in originalposition. 1

scribed, a plurality of translating mechanisms operable in a determined sequence, and" V a timing device opera'ble in one direction at the start of the sequence of operations and no I operable in the other directionat'the end of said sequence of operations.

4, In a control system-of nisms operable" in a 1 determined sequence,-

7 the class v I scribed, a plurality of translatingmecha' timing devices for'regulating the period of operation of each of said translating mechanisms, and means for operating one of said timing devices in one direction at the start.

of a sequence of operations and in the other direction at the end of a sequence of operations to thereby control the starting and stopping of the sequence of operations.

5. In a control system of the class described, a plurality oftranslating mechanisms operable in a determined sequence, timing devices for regulating the period of operation of each of said translating mechanisms, means for operating one of said timing device in one direction at the start of a sequence of operations and in the other direction at the end of a sequence of operations to thereby control the starting and stopping of the sequence of operations, and means for render mg the timing means inoperative toprolong the period of'operation of any of said trans- *7. In a control system, the combination of a plurality of translating mechanisms operable in a determined sequence, means for starting the operationofone of said mechanisms upon the cessationot-the operation of the preceding of said mechanisms, timingmeans associated With'each of said mechanisms for determining the period of operation of its respective mechanism, starting means operable to beginthe sequence of operations, and means for operating said starting means at the end of a sequence of operations to end the sequence of operations.

8. In a control system of the class described.

the combinationof a 'oltin mechan sm 0 7 sand riddle, means for swingingsaid riddle into and out of position, means for control ling .the operation of said jolting mechanisms, and means operatedby the swinging of said riddle into position for rendering said controlling means operative.

mechanism, means for clamping amold "on I said su ortin mechanism, a riddle movable into and out of position with respect to the mold, and means operated Whenthe riddle is moved into position for controlling the operation of said clamping means.

10. The combination of a mold support ng mechanism, means for clamping a mold on said supportingmechanism, a riddle movable into and out of position with respect to the mold, means operated When the riddlev is 9. The comb nation of a mold supporting.

moved into position for controlling the opration of said clamping means, and means for.

releasing said clamping means.

llrln a control system of the class described the combination or a mold supporting mechanism, means for feeding sand to the mold and for oltmgthe mold, a sand riddle movable into and outof position With re-.

'spect to the mold, means for controlling the operation of said sand feeding and: jolting means, andmeans operated When the riddle is moved out of positionfor rendering said controlling means operable. T 4

12. In a control system of the class described the combination of a plurality of operating mechanisms,a plurality of timing devices controlling the duration of time of operation or". said mechanisms, anindependent motor for operating each 'of said timing de-' vices, and means controlled by one of said timing devices and operable upon the cessation of operation thereoffor starting the motor of another timing device.

18. In a control system of the class described the combination of a plurality of operating mechanisms, a plurality of timing devices controlling the duration of time of operation of said mechanisms, anindependentmotor for operating each of said timing devices, means controlled by one of saidtiming devices and operableupon the cessation of operation thereof for starting the motor of another timing device, and r means independent of the timing devicesfor controlling theoperation of said motors.

14. In a control systennthe combinationofa plurality of. translating mechanisms operable in a determined sequence, means for starting the operatlon'of one of said mechanisms upon the cessation ofthe operation of the preceding of said mechanisms, timing means associatedwvith each of said mechanisms ior determining the period of operation of; its respective mechanism, starting means operable to begin the sequence of operations, means for operating said starting means at the end of a sequence of operations to end the 'sequenceol operations,-and'means for controlling the operation of any one of said mechanisms independently of said timingmeans. 7 V

: In a control system of the class described the combination of mold stripping and clamping mechanism, sand feeding mechanism, and jolting mechanisnne'ach adapted to be operated n relative sequence, means for starting the operation of each mechanism in its proper sequence and upon the cessation of operation of a preceding mechanism, and timing means for determining the duration of operation of each or said mechanisms} 16, In-a control system of the class described the combination of aplurality of pneumatically operated mechanisms, a source of an! pressure for said mechanlsm, means ling said switches, means automatically operable uponthe cessation of one timing device for starting the operation of another timing device, and manually operated means for independently controllingsaid', switches.

18. The combination. of a motor operated riddle,

means operated by said support inits movement for controlling theoperation ofthe rid dle, motor.

19. The combination of a motor driven riddle, a movable support for carrying the riddle to and from its operating position, anda switch actuated bythe supportin its movement for controlling the riddle motor. 7

20. The combination ofa motor operated a movable support for carrying the riddle, riddle into and out offoperating position, means operated by said support in itsmovement for controlling the operation of the riddle motor. a molding machine, s'and feeding mechanism for supplying sand to said moldring machine, and means operated by said riddle support in its movement for control-T ling the operation o-f said molding machine.

. and said sand feeding mechanism.-

21. The combination of a motor operated riddle, a movable support for carrying the riddle into and out of operating position,

'mcans operated by said support in its move inent'for controlling theoperation of-th'e riddle motor, a molding machine, sand feeding mechanism for supplyingsand to said molding,macliine, means operated by said riddle support inits movement for control-1 ling the operation of said molding machine] and said sand feedingmechanism, and tiniring mechanism for determining the duration a movablesupport for carrying the riddle into and out of operating position, and.

mechanism and means controlling the operat 'ing of said fluid operated mechanism comprising a-longitudinally movable "screw,

means for, rotating said screw, means operable by engagement with the screw to compel itslongitudinal movement while the screw rotates, means for returning the screw longitudinally to normal position on the release of said engaging means, and a switch operated by the screw in its longitudinal movement for controlling the screw driving means.

24. The combination of-a longitudinally; movable screw, a. motor for rotating the fscrew, an electromagnetically operated device adapted to engage the screw and "compel its longitudinal movement inone direction when the screw is rotated, means for, re:

turning the screw longitudinally tonormal position when released from saiddevice, and a switch operated by said screw for COI1 IfQ1- ling vice.

said electromagnetically operated de: 1

25.1 The combination of a longitudinally" movable screw, a motor: for, rotating the screw, a member adapted when engaged with the screw to compel the longitudina'lfmovement of the screw in onedirec'tiommeans op-' erable when said memberis disengaged from the screw to returnthe screw to normal p0 'sition, an electromagnet for operating said-- member, and means operated by' thescrew in said electromagnet.

26. The combination shaft and to move longitudinallythereof, a. half-nut adapted to engage said screw and rection, an electromagnet for operating said "half-nut to compel the screw to move longitudinally in one direction,-'and means operable when "the screw reaches the limit 'of' said" ,movement for controlling the screw longitudinally to normal position when" disengaged bysaid half-nut; i

' 27. The combination of a plurality of fluid "operated mechanisms, aplurality of electro-- magneticallyoperated switches controlling said mechanisms, means for controll ng said 5 switches to operate said mechanisms in a predetermined sequence, and timing mechanism for determining the duration of operation of each of said mechanisms.

, Lewis EGGE T,

ofoperation of saidsand feeding mechanism" 7 and said molding machine.

22. The combination of a plurality of fluid l operated mechanisms, timing mechanisms for controlling said fluid operated mechanisms,

means for starting one of said timing mechal nisms in operation, and means, controlled upon the cessation of said timing device for startinganother timing deviceein operation.

7 23.- The combinationof a fluid operated of motor driven shaft, a screw adapted to be rotated by said its longitudinal movement for controlling cause its movement longitudinally in one di ice 7 

